Hydro Thrunder, single player game an excellent game for on-line.
Each river track has secret short cuts to knock off your time and beat the pack of boats ahead of you. To do so, I suggest you should get similar of each course you race on. Or go back take your time to find the short cuts this way you where they are. However, you maybe come across of icons spinning 360 around above you or on the water. Some these icons are not visible. There are some that are hidden; places where you lease suspected. Few of these icons unlock achievements and other rewards. Remember, when you unlock the series of boats the handling will get a little tougher, and faster. The tracks don't change at all, just the boats do. It's best to use the novice boats first.
When racing live arcade mode all boats, paint scheme and tracks are unlock. While in single player mode these items are lock until you obtain the credits to lock them. I've enjoyed this arcade game and will continue to play it. This game is not on a disk. You'll need to download for 1200 game credits to play it. There is a demo to play.
Cheers!
MedicBigDog